The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the inventors hereof, to the extent the work is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted to be prior art against the present disclosure.
When operating in an infrastructure mode, wireless local area networks (WLANs) typically include an access point (AP) and one or more client stations. These WLANs operate in either a unicast mode or a multicast mode. In the unicast mode, the AP transmits information to one client station at a time. In the multicast mode, the same information is concurrently transmitted to a group of client stations. Development of WLAN standards such as the Institute for Electrical and Electronics Engineers (IEEE) 802.11a, 802.11b, 802.11g, and 802.11n standards has improved data throughput by allowing transmissions across frequency bandwidth. In such implementations, a group of client stations can share the same bandwidth for data transmission. For example, the 802.11ax standards adopts orthogonal frequency division multiple access (OFDMA) to support multiple users in the same bandwidth, and each user is scheduled with a resource unit (RU) occupying a number of subcarriers in frequency.
A resource allocation mechanism is needed to allocate the available RU to each client for transmitting data frames to the AP. For example, the AP and/or the client station need to know how much bandwidth out of a channel is allocated to a specific user. Specifically, when a large number of client stations share a transmission channel to transmit with a low-cost AP (e.g., home use), the existing resource allocation signaling mechanism may be inefficient in terms of bandwidth utilization. For example, the existing resource allocation signaling mechanism requires a large amount of resource allocation signaling information transmitted with a data frame. The data bits used for signaling may take up a significant amount of bandwidth, which reduces transmission efficiency and complicates the scheduler.